There's a must-read interview with Coyote Frontier author Allen Steele over at The Space Review, where he talks a lot about the future of space exploration. (And makes a strong statement in favor of "boots on the ground" space travel, as opposed to just sending out probes.) One of the interesting bits comes when Steele discusses the 1967 Outer Space Treaty, which prohibits claiming sovereign territory in space:

You have to remember how things stood 45 years ago when the United Nations formulated the space treaty. The US and the USSR were locked in a cold war that was not only on the perpetual verge of becoming hot, but also extending beyond Earth. Remember the scene in 2001: A Space Odyssey when we see orbital nuclear weapons? That was a real concern when that movie was made. So was the notion that the winner of the space race would not only plant its flag on the Moon, but also claim it as national territory. So the treaty has necessary to prevent an international crisis from occurring if either side decided to pursue an arms race in space, and to that degree it's been successful. When a Russian satellite passes above us, the most lethal thing it has aboard is a camera.

Things have changed quite a bit since then. Not only has China become the third superpower to gain manned spaceflight capability, but Europe, Japan, India, and Brazil have also developed unmanned space technology, and North Korea, South Korea, Vietnam, and Indonesia are pursuing the same. Of those countries, both China and India are actively pursuing lunar exploration; for the US, returning to the Moon has been a matter of taking two steps forward then one step back for the last forty years, and that's giving those other two countries an enormous window of opportunity. And we're only discussing government-funded space initiatives. Space industry is something else entirely. SpaceX has no intention of settling for just being able to send cargo to the International Space Station, and neither are any of its competitors.

I think we're approaching a true Space Age that will make past efforts look like a prelude. If that's true, then at some point the 1967 space treaty will become obsolete. Not useless, just ill-suited for a new reality. The farther humankind ventures from Earth, the less enforceable the treaty will be; it will be as absurd as the Boston City Council trying to pass leash laws for San Francisco.

There's tons more stuff at the link, and it's well worth reading. [The Space Review]